Ammunition belt link guide mechanism for automatic guns



APHl l2, 1949. E. c. HoL'roN v 2,466,893

` AMMUNITION BELT LINK GUIDE MECHANISM A FOR AUTOMATIC GUNS Filed April 9, 194s 2 sheets-sheet 1 E. C. HOLTON AMMUNITION BELT LINK GUIDE MECHANISM FOR AUTOMATIC GUNS 2 Sheets-Sheet 2 April l2, 1949.

Filed April 9, 1945 25v f? ff 2/ 715/ l I v L VWM/70e,.- l y fau/HP0 @4971, HOLTON.,

Patentecl pr. '12, 1949 AMM'UN-ITION BELT LINK GUIDEMECH.-

AMIS-M FOR AUTOMATIC GUNS Edward Cyril Holton, LosfAngeles,` Calif.

Application Aprilq9, 1945,.S.eral.No. 581,258.

19 Claims.

My .invention relates to automatic guns and, more particularly, to an improved cartridge-.guid- .ingmechanism therefor. It isl parti-cularlyuseful in connection with Browning-type guns and will be exemplified as. applied thereto,- though-it should be Aunderstood that it caribe adapted=-with,slignt modi'lcations,.l to other automatic guns.

"The .ammunitionbelt fed to automatic .guns usually comprises .a rplurality of cartridges-suitably connectedtogether,.modern practice involving. the use. of a disintegratingftype. belt in which the cartridges are connected by metallic links. lThe linked ammunition advanced` stepby. step along a transverse feedway kby a-sui-tablepawl mechanism. The foremost cartridgeis moved into an extraction position upon. Contact .with the usual cartridge v'stops .preparatory vto .extraction from the belt .and insertion. into the, gun barrel. f

being below the level of the ieedway. Al'soduring this forward movement of the. bolt,j the next Aor" following cartridge of the' belt is advanced into extraction position. 'During such advancement, it-isdesirable that the link that .hel'd the previous.- ly extractedv cartridge be'used for the proper placing of the following: cartridgein correct ,position for extraction.

'It is; an object of the. present invention to provide a novel structure 'for guiding,A in a positive manner; thel-inks employedin an ammunition belt thelinks, bythe gun-feeding. mechanism. EX.- traction of each cartridge from the.y belt freesa link, yand the .present invention provides a positive guide therefor to preventmi'salignment and binde i'ng such as frequently occurs, particularly if .the link is permitted to move forward upon release. Such forward movement is prone. totakeplace, particularly if the .muzzle of, .thegunis depressed,

.asmust oftenbe the case when thegun is mounted in an airplane wing or .in a, turret.

yIt is an object of the present invention -topro- -vide ya .link-.guiding .mechanism :employing :1.a :plunger whichadvances. inwardly opposite. a; 1in-k .during ornimmediatelyz; after its; release torretain A.:

during and after extraction of the cartridges; from 5&0

:contacted by thebolt or extractor. .tests have. shown. .that the present invention will .overcome jamming becauser of the .presenceoi rshort rounds in. the .ammunition belt, while, at. the

. 24 the link in proper alignment and prevent binding, .which might result. stoppage of the4 gun.. yThis ,plungeracts ,in .thev nature ofta movable gate bounding .al linkrreceiving passage, and. it isan objectof the presentv invention to providea movable nremben-actuated automatically by the operation of the gun, to form one boundary of .a link-receiving passage. It is a further object of the invention to provide. such a movable plunger which assists in maintaining, proper. alignmentof the ammunition belt during feeding along the feedway. In this. connection, the aligning of a forward or leading portion of each link, While the rear` or trailing portion of the link Ais still attached to the next cartridge, -serves to guide the entire movement of `the ammunitionbeltand results in improved perform-ance and firing characteristics of thegun.

The presence in the belt of a short round will often jam or stop the gun. This may result `in a very serioussituation, particularly if the gun is positioned remote from the gunner, e. g.,- in the wing of an airplane, as it is thenvim-possible to extract manually the faulty cartridge or round and resume ring. A shortv round is` the result of a decrease in overall, dimension 0f lthe cartridgerand may result from defective manufacture or accidental inward displacementaof the @bulletzinthe case during-:handling of, the ammunition. In some instances, the round-may be .shortened in the feedway if the bolt strikes the rear of. the-cartridge or'when the extractor cams upward over the. rear of the cartridge case. I In the usual automatic gun, the nose ofreachxbullet slides along, or. immediatelyadjacent,V a iront .wall

of the feedway. Forward pressure `appliedfto the -rear of the cartridge case-may thusA besufcient to force the bullet farther into the case,- particularlyy if the-forward end ofthe case; is split or improperly crimped on-the bullet, 'thus resulting in a short round. `A short round will jam or stop the gun ifthe oannelure of' thecartridge is disposed beyond tne `reach of the extractor.

It is an objectoi the present invention tomaintain the cartridge cases in alignment so that their lcannelures are aligned and within reach lof the extractor, this being accomplished byv proper alignment of the links to prevent the cartridges from moving too far forward in the feedway when Extensive same time not interfering with .the vnorn-ial, opera- 3 tion of the gun and without decreasing its firing rate.

In conventional automatic guns, the extraction position of the leading cartridge is determined by engagement with front and rear cartridge stops. Also, a link stripper is usually provided to retain the link when the cartridge is being extracted. Conventionally, these cartridge stops and the link stripper are separate units and must be separately Withdrawn for inspection or for changing the gun from right-hand operation to left-hand operation, or vice versa. This operation is time consuming and difficult to perform, particularly if it must be accomplished by gloved hands.

It is an object of the present invention to provide a readily removable unitary attachment for an automatic gun, and to which the cartridge stops, the link stripper, and/ or a link guide means of the invention are secured, thus facilitating in" sertion, withdrawal, and shifting of these elements. In this connection, the invention has among its objects the attachment of the cartridge stops, link stripper, and/ or a link guide means to a base plate to form a unitary structure which can be quickly inserted `for either right-hand or lefthand operation of the gun, thus providing a unitary structure which can be easily handled and which will prevent loss or dropping of .s all when the gun is being changed from right-hand to left-hand operation, or vice versa.

It is another object to removably connect a link-discharge chute to such a unitary structure to facilitate shifting the position of the chute when changing from right-hand to leftdiand operation, or vice versa.

Further objects and advantages of the invention will be evident to those skilled in the art from the following description of exemplary' embodiments.

Referring to the drawings:

Fig. 1 is a fragmentary top view of a machine gun with cover removed and showing the invention in place;

Fig. 2 is a vertical sectional view, taken along the line 2 2 of Fig. i, but showing the gun in partially raised position;

Fig. 3 is a fragmentary side View of the gun, taken `as indicated by the arrow 3 of Fig. 1;

Fig. 4 is a section taken along the line 4--4 of Fig. 3, and showing the invention as used for lefthand feed; showing also (by dotted lines) the position of the invention for right-hand feed;

Fig. 5 is a perspective view of the embodiment of the invention shown in Figs. 1 to 4, and indin cating its relationships to a cartridge in the extracting position;

Fig. 6 is an elevation of the embodiment shown in Fig. 5;

Figs. 7 and 8 are, respectively, plan and end views, Fig. 7 being partially in section and being taken along the line 'l-l of Fig. 6;

Fig. 9 is a perspective disjoined view of an alternative embodiment of the invention;

Fig. 10 is a rear view of the embodiment of Fig. 9, taken as indicated by the arrow lil and Fig. 11 is a fragmentary perspective view of another embodiment of the invention in which the plunger carries a curved link-contacting member.

The complete structure of the machine gun and the operation thereof will not be described in detail as these are readily understood by those skilled in the art. The drawings show only those portions of an exemplified machine gun structure pertinent to the invention.

the cover of As shown, the machine gun includes the usual side plates i6, between which is positioned a forwardlydisposed trunnion block l I. The machine gun is provided with the usual hinged cover l2 which, when closed, forms the upper boundary of a transverse feedway I3, along which is automatically advanced an ammunition belt l5 of conventional construction, shown as comprising a plurality of cartridges I6 interconnected by links il. Each link Il includes a bifurcated forward or leading portion bent to surround the leading cartridge of each pair to form two loops I3 and I9, respectively providing front and rear faces 2i? and l!! Each link also includes a rear or trailing portion bent around the adjacent cartridge to form a loop 22 hinged to this cartridge. The loops I8 and i9 frictionally engage the case of the leading cartridge, this cartridge case being indicated by the numeral 25, the forward loop lil being frustoconical to engage the usual tapered portion of the case In the forward end of each case 25 is the usual bullet or projectile having a nose 2i'.

The gun provides a barrel 3U having a rifle bore 3l at an elevation below the feedway I3.

Upon recoil, the barrel 3U moves rearward a limited extent and operates the breech mechanism of the gun, including a longitudinallymovable breech bolt 32 which moves rearwardly a greater distance than does the barrel 30.

The ammunition feed mechanism of the gun includes an actuating pawl means 33 carried by the cover iii and actuated by a lever 3ft having a follower riding in selected grooves 35 of the breech bolt 32. The actuating pawl means 33 successively engages the cartridges to advance the belt along the feedway I3, there being an auxiliary pawl means, not shown, for retaining the cartridges against opposite movement The leading cartridge of the belt is advanced to an extraction position corresponding to the cartridge A of Fig, 1, which extraction position is determined by the invention, as will be later described. An extractor 36 is carried by an arm 31 pivoted to the breech bolt 32. During forward motion of the breech bolt, the extractor cams upward over the rear end of the cartridge and enters the cannelure 38 thereof. As the breech bolt 32 moves rearward, the extractor withdraws the cartridge from the belt and forces it downward into a T-slot 39 on the forward face of the breech bolt, while at the same time expelling the previous cartridge case. As the breech bolt moves forward, it forces its retained cartridge into the barrel 30 for firing. A new cartridge is moved into the extraction position during the forward movement of the bolt.

On opposite sides of the gun are mounted correspondinglyformed brackets 42 providing a series of spaced lugs 43 traversed by a removable pin 44. Conventionally, the lusual stop members and link stripper are individually mounted in the spaces between these lugs, being held in place by the pin 44.

The preferred embodiment of the invention includes a cartridge guide means or a link guide, best shown in Fig. 5 and comprising a unitary guide structure indicated generally by the numeral 5D. This unitary guide structure is adapted for right-hand or left-hand gun feed and comprises a base plate 5I with lugs 52 and 53 spaced longitudinally of the gun axis to be disposed between pairs of lugs 43 or immediately beyond the foremost and rearmost of these lugs. Pairs of lugs 52, 53 are disposed along both upper and lower portions of the base plate 5| and veach suchflugis'fprovided-with a. groove 54. Whetheremployed for left-hander right-hand feed, the grooves: of thelowermost lugs receive the pin'M tozretain the guide structure 50- in position attthatend of the feedway I3 toward which'the ammunitionfmoves. As shown in full lines in Fig.f4,ithe guide structure 56 is adapted for left-.hand .'feed. When employed for righthand feed,y itwis -merely upturned and inserted as! indicated by dotted lines 56. In either instance', the cover I2, when closed, aids in retainingthe guide structure 56. in proper position,

@Fixed rigidly -to the base plate 5I is a rear cartridge stop-58 and a front cartridge stop 59, yrespectively engaged by the case and bullet. of the cartridge when in extraction position. In addition, a 'lin-k stripper 60; is also rigidly conne'ctedf" to the base plate and can serve as a cartridgeston `'Its innermost end has a semicircular channel conforming in shape with the periphery of the case. The lip of the link stripper immediately around this semi-circular channelengages'the rear side 2| of the loop I9, which '-frictionallyengages thev cartridge case, all in suchmanner astowretain the link from rear- 4ward motion lwhen the cartridge is extracted. Preferably, the cartridge stops 58, 59 and the link vstripper 60 areintegral with the base plate 5I. If desired, a web 62 may extend between and further rigidify the cartridge stop 58 and the link'strpper `6D. The height of the cartridge 'stop l59-is such that the lower face thereof rests on the oor of the feedway I3 and the upper face thereof is contacted by the cover I2.

Aliso attached to, and preferably integral with, the base plate 5I is a guide member 65 in which -reciprocates a gate or plunger 66 acting as a link-guide member. The guide member65 may be integral with the yfront cartridge stop 59 as =shown,- or separate therefrom. It provides a guideway, lshown as T-shaped in cross section infTF-ig. 6, comprising a guide passage 68 and a side passage 69 opening longitudinally thereon, bothpassages extendingsubstantially parallel to tlsie"direction-of ammunition advancement along thefeedway -I 3.

Pit-least a portion of the plunger 616 conforms in cross-sectional shape to the guideway to slide therein. As shown, the plunger yS6 includes a ybody'portion I0 sliding-in the guide'passageand a side portion 'Il extending from, and preferably slidably-journalled in, the side passager 69. The sideV portion 'II extends beyond the guide member 6*'.ivandprovides a link-contacting face 'I3 spaced from the link stripper-68 a distance :slightly greater than the width of the links between front and rear faces 20 and 2| to provide, ybetween the facef'I3 and the link stripper 60, a link-receivingpassage 'I4 guiding the released linksto alink-discharge opening l5 of the base plate; 5|. The forward portion 'of the link-contacting face 'I3 is curved or beveled to provide a curved portion ,16 terminating in a car-tridge- .engaging endv portion Il at ytheinnermost end `offthe plunger 66.

Means is provided for resiliently urging the .plunger .66 inward, i. e., toward theadvan'cing ammunitionrmoving along the feedway I3. In the preferred construction, the plunger 66 is hollowv from near its `end portion 'I'I to its base to .receive alight spring 80. The base of this spring seatsiagainst a plug BI secured in position in the guide passage 6,8, as bya transverse pin 82. Thislplug preferablyvcarries a rod 83 centering the spring.. vil!! and 4.of such lengthv that its end forms a stop means limiting the movement-of the plunger 66 upon engagement with theend wall of its hollow portion. The stop means may limit the plunger movement to help determine the extraction position of thecartridge but., preferably, is positioned to permit a slight overtravel of the plunger beyond its position when its end portion 'II is in engagement with a cartridge in the extraction position, whereby the normal retracted position. ofv the plunger is determined bysuch cartridge engagement.

The maximum advanced position yof the plunger 6.6 under the action of the spring `80, is determined by a stop means, best shown in Figs. Gand' 7. As therein-shown, the base end of the plunger 66 carries a stopmember 85 sliding in an auxiliary side'passage of 'the guideway. A pinfBI extends into the auxiliary side passage 86 through the wall carrying the front cartridge stop 59- and into the path of travel of the plunger-carried stop member 35. The advanced position of the plunger, determined by the stop member'f85, -is suggested by dotted lines 88 of Fig.y 1 and should be such 'that the cartridge-engaging end portion il, and preferably the entire curved portion -16 of the link-contacting face' 13, is disposed beyond the center line of the cartridge A inthe extraction position. The advanced position may be such as to permit the plunger 66 to engage cartridge B ready to move into the extraction position, but this is not necessary and the preferred. arrangement is to stop theplunger before its end portion 'Il engages cartridge B.

The base plate 5I removably :carries avlink-discharge chute 90, which may be of any desired form and which receives the released links discharging through the link-discharge opening 'I5 of the base plate. As shown in Figs. 1, 3, 4, and 5, this chute 30 provides channel-shaped end walls 9E spot, welded tocover members I92 to provide a chute passage 93, preferably curved downward and inward as :best shown in vFig.:4. `A frame-like attachment member B4 is spot welded to the upper ends of the chute rwalls and provides flanges symmetrical with threaded openings of the base plate 5I, which 'openings receive screws 96. Whenchanging the guide |structure 50 from left-hand to right-hand feed, the Screws 96 are removed and the link-discharge chute k90 is re-attached to the now-inverted guide structure 50 in the dotted line position 91 of Fig. 4.

The operation of the invention is as follows. Under the action-of the actuating pawl means 33, the leadingV cartridge is moved into its extraction positiondetermined by contact between the front stop 59 and the bullet;` also, by contact of the cartridge case with the rear stop 58 and `the link stripper 60. When the cartridge isin its extraction position, the plunger 66 is in'its retracted position shown inl Figs. 1 and 5.' The extractor 36 thenmoves forward and cams up,- wardly over the rear end of the cartridge. Any tendency to force the cartridge forward vis impeded by contact between the front face 20 of the leading and partially-released link andthe link-contacting face 'I3 of the plunger. AIn'this connection, it should be, noted that the frusto- -conical forward loop I8 of the link engaging this cartridge prevents forward movement of Ithe cartridge with respect to this link. The loop '22 of the partially-released leading link slides along the cartridge case 25, a very small distanceuntil it engages the loop I9. Thereafter, any forward pressure applied to the cartridge is transmitted `from the loop22ntot1r1e` loop- I8 and thence to tridge reaches said extraction position; and a light .spring resiliently urging said plunger to ward said leading cartridge.

'3. A combination as `defined in claim 2, in which said stop means includes a link stripper disposed yto contact a cartridge in said extraction position on4 one side of its connected link, and 'in 'which said plunger is spaced from `said link stripper to engage said cartridge on the opposite side of-said link.

4. A combination as defined in claim 2, in which said stop means includes a link stripper disposed-to contact a cartridge in said extraction position on one side of `its connected link, and in which' said plunger is spaced from said link stripper to engage said cartridge on the opposite side of said link, said plunger providing a linkcontacting face spaced from said link stripper a distance only slightly greater than the widthoi said'link measured longitudinally of said cartridge to form a link-guiding passage.

45. 'In an ammunition guide means for an automatic 4gun having a transverse feedway, having means for advancing link-connected cartridges therealong to dispose the leading cartridge in an extraction position, and having an extractor for extracting this cartridge from its associated links when-this cartridge is in said extraction position, said ammunition guide means comprising: a plunger A'disposed to be in engagement with said leading cartridge when in said extraction'position; and means for quickly extending said plunger in a direction substantially counter to the direction of advancement of said link-connected cartridges as soon as said extractor withdraws said leading cartridge from its connecting links.

6; An ammunition guide means as defined in claim 5, in which said last-named means -includes a spring urging said plunger into resilient engagement with said leading cartridge until Withdrawn by saidextractor, said spring then advancing -said Vplunger toward the next cartridge, said plunger moving at least to the centerline of a cartridge when disposed in said extraction position.

7. An ammunition guide means as defined in claim 5, in which said plunger is disposed to extend "in front of an unreleased link on a cartridge'in said extraction position, and in which said plunger provides a face immediately forward of such link to resist forward motion of the link and cartridge axially of said gun and thus maintain the rear of said cartridge in proper position for engagement by said extractor.

8. An ammunition guide means for an automatic gun adapted to advance an ammunition belt comprising link-connected cartridges along a transverse feedway to dispose the leading cartridge in an extraction position, said ammunition guide means including: a guide member positioned beyond said extraction .position and providing a guideway extending toward the advancing cartridges; a plunger having a cartridgeengaging portion, said plunger being inwardly movable along said guideway from .a retracted position in which said cartridge-engaging portion contacts a cartridge in said extraction position to an advanced position in which said portion extends beyond the center line of a cartridge when in said extraction position to contact a cartridge moving toward said extraction position; stop means for limiting the inward movement of said plunger when in said advanced position; and a spring urging said plunger from said retracted position toward said advancedV position.

9. An ammunition guide means for an auto-V matic gun adapted to advance `an ammunition belt comprising link-connected cartridges along a transverse fecdway to dispose the leading cartridge in an extraction position, said ammunition guide means including: a guide member positioned beyond said extraction position and providing a guideway extending toward vthe advancing cartridges; a plunger slidable in said guideway and having a cartridge-engaging endportion and a link-contacting face to one side' of said guideway, said link-contacting face beingmeans then moving said plunger again inward to move said link-contacting face adjacent thel link being released by extraction of its associated cartridge to retain this released link in alignment with the other links of said ammunition belt.

l0. An ammunition guide means for an automatic gun adapted to advance an ammunition belt comprising link-connected cartridges along a transverse feedway to dispose the leading cartridge in an extraction position, said ammunition guide means including: a guide member positioned beyond said extraction position and lproviding a guide passage extending toward 'the advancing cartridges and a side passage open'-Y ing on said guide passage; a plunger providing a body portion slidable in said guide passageand providing a side portion extending from said side passage, said side portion providinga link-contacting face movable adjacent the'links of said ammunition belt, said body portion pro-y viding a cartridge-engaging end portion; and means for resiliently urging said plunger 'inwardly to dispose said end portion in the pat'h of a cartridge advancing to said extraction posi#- tion to be contacted thereby, said end portion remaining in contact with such cartridge until' it reaches said extraction position and until lit is subsequently extracted from its connected links, said resilient means then moving said plunger again inward to move said link-contacting face adjacent the link being released by extraction of its associated cartridge to retain this release-d link in alignment with the other links of said ammunition belt.

11. An ammunition guide means as defined in claim 10, in which said plunger is hollow, and in which said resilient means comprises a spring disposed in the hollow plunger.

l2, A guide structure for an automatic gun in which link-connected cartridges are advanced along a transverse feedway to dispose the leading cartridge in an extraction position, guide structure including: a base plate; connection means for removably connecting said base plate to said gun at the end of said transverse feedway toward which said cartridges move; a link stripper rigidly secured to said base lplate; a guide member rigidly secured to said base plate; a plunger movable relative to said guide member; and means for resiliently urging said plunger toward the leading cartridge advancing toward said extraction position, said link stripper and said plunger being spaced to deiine a link-receiving passage guiding the links as they are released upon extraction of the cartridges.

13. A guide structure as dened in claim l2, in which said base plate provides a link-discharge opening communicating with said link-receiving passage.

14. A guide structure as defined in claim 12, in which said base plate provides a link-discharge opening communicating with said link-receiving passage, and including a link-discharge chute carried by said base plate for receiving the released links.

l5. A guide structure as defined in claim 12, including a link-discharge chute for receiving the released links, and means for detachably connecting said link-discharge chute to said base plate, and in which said connection means includes means for detachably connecting said guide structure to said gun for selective right-hand and left-hand feed of said cartridges thereto, said means for detachably connecting said linkdischarge chute to said base plate being reversible to accommodate the discharge of said links when said guide structure is disposed for either right-hand or left-hand feed.

16. A guide structure as defined in claim 12, including a stop means for limiting the motion of said plunger toward the leading cartridge advancing to said extraction position to limit the advancing movement of said plunger to a position in which at least a portion of said plunger traverses the center line oi a cartridge lwhen disposed in said extraction position.

17. A guide structure for an automatic gun in which link-connected cartridges are advanced along a transverse feedway to dispose the leading cartridge in an extraction position, said guide structure including: a base plate removably connectable to said gun at the end of said transverse feedway toward which said cartridges move; and means carried by said base plate vfor forming a link-receiving passage, said means .including walls carried by said base plate in spaced relationship to bound said link-receiving passage, said walls extending along said feedway toward said extraction position, one of said walls providing a curved face to provide a link-receiving passage which ares in Width toward said extraction position. i

18. A unitary guide structure for attachment to an automatic gun for selective right-hand and left-hand feed of link-connected cartridges to and along a transverse eedway of said gun to dispose the leading cartridge in a predetermined extraction position, said gun including bracket means on opposite sides thereof adjacent the ends of said transverse feedway, said unitary guide structure including: a base plate providing a linkdischarge opening; a first member carried by said base plate and of a height to t in either end of said feedway, said rst member being positioned by said base plate and providing an inner end engageable with the leading cartridge to determine said extraction position; a second member carried by said base plate and of a height to t in either end of said feedway, said second member being positioned by said base plate to extend in said feedway in spaced relationship with said first member to define a link-receiving passage therebetween, said link-receiving passage extending to said link-discharge opening of said base plate to guide the released links in their movement to said opening, said members providing link-guiding walls facing each other and bounding said link-receiving passage; attachment means at thel bottom of said base plate for removable connection to said bracket means on one side of said gun to mount said guide structure on the gun in a iirst position with saidirst and second members of the guide structure extending n said feedway from one end thereof; and attachment means at the top of said base plate for removable connection to said bracket means on the other side of said gun when said guide structure is in inverted position to mount said guide structure on the gun with said first and second members extending in said feedway from the other end thereof.

19. A unitary guide structure as dei-ined in claim 18 including also at least one cartridge stop rigidly secured to said base plate and spaced from said first and second members to extend in said feedway and providing an end surface engaged by the leading cartridge to determine itsV extraction position,

EDWARD CYRIL HOLTON.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Norway Oct. 24, 1927 

